/Engine/Source/Runtime/SignalProcessing/Public/DSP/FloatArrayMath.h
RowIndex determines which row is being set. StartIndex denotes the offset into the row where the OffsetValues will be inserted. OffsetValues contains the contiguous chunk of values which represent all the nonzero elements in the row.
void SetRow ( const int32 RowIndex, const int32 StartIndex, [TArrayView](API\Runtime\Core\Containers\TArrayView)< const float > OffsetValues )